I suspect that the definition of 'high-ranking ninja' as applied to members of the council is one of two circumstances:
a) by invitation of the Hokage, either permanent or temporary
b) because no one wants to tell them to "No."
For example, would you seriously want to tell Gai he couldn't attend a meeting of the Council? Sure, he'd be annoying. But that's not as bad as having him picket you 24/7 to demand access to the Council's meetings.
D for Drakensis
You're only young once, but immaturity is forever.
a) by invitation of the Hokage, either permanent or temporary
b) because no one wants to tell them to "No."
For example, would you seriously want to tell Gai he couldn't attend a meeting of the Council? Sure, he'd be annoying. But that's not as bad as having him picket you 24/7 to demand access to the Council's meetings.
D for Drakensis
You're only young once, but immaturity is forever.